Truck and caravan permanently parked on street and a pita can anything be done?

First of all one of their neighbours has 5 vehicles so at least 3 are on the road which has meant that when you turn into my street, because of all his cars/vans, you have to check theres nothing coming down the street before you drive up. I'm used that but now one of his neighbours has got their caravan on the road now and another has a small truck, neither of which have ever moved for over a month.

This means that now when I want to check if a car is coming down the street I can't as the caravan and truck block the view up the road and when I do take a chance and there is a car coming down there's nowhere to pull in because of all the vehicles of the 3 neighbours combined

I don't want to start saying anything to them if I have no right to do, just want to know if there's anything that can be done?